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IV.C.1. (XIII.D.1.)

Compare vibrational frequencies in CCCBDB for C4H4N2 (Pyrazine)

MP2/CEP-121G

Frequency in cm-1
  Calculated   Experimental
Mode Number Symmetry Frequency diff Symmetry Frequency Comment
1 Ag 3106 51 Ag 3055  
2 Ag 1487 -93 Ag 1580  
3 Ag 1201 -32 Ag 1233  
4 Ag 923 -93 Ag 1016  
5 Ag 581 -21 Ag 602  
6 Au 692 -268 Au 960  
7 Au 294 -56 Au 350  
8 B1g 866 -61 B1g 927  
9 B1u 3083 71 B1u 3012  
10 B1u 1419 -64 B1u 1483  
11 B1u 1090 -40 B1u 1130  
12 B1u 955 -63 B1u 1018  
13 B2g 813 -170 B2g 983  
14 B2g 691 -65 B2g 756  
15 B2u 3099 29 B2u 3069  
16 B2u 1363 -48 B2u 1411  
17 B2u 1151 2 B2u 1149  
18 B2u 1018 -45 B2u 1063  
19 B3g 3080 40 B3g 3040  
20 B3g 1428 -97 B3g 1525  
21 B3g 1320 -26 B3g 1346  
22 B3g 672 -32 B3g 704  
23 B3u 741 -44 B3u 785  
24 B3u 403 -15 B3u 418  
The calculated vibrational frequencies were scaled by 0.976

See section XIII.C.3 List or set vibrational scaling factors to change the scale factors used here.
See section III.B.3.c Calculate a vibrational scaling factor for a set of molecules to determine the least squares best scaling factor.
See section III.B.3.b List of vibrational scaling factors and their uncertainties for information on where the above scaling factor is from.